Visceral fat, the hidden fat stored deep in the abdomen, may be an early predictor of Alzheimer’s disease, with new research suggesting a link between this type of obesity and the buildup of brain proteins associated with the disease. The findings, presented at the Radiological Society of North America’s (RSNA) annual meeting, reveal that the risk could manifest up to 20 years before symptoms appear.
The Link Between Visceral Fat and Alzheimer’s
A team of researchers at the Mallinckrodt Institute of Radiology at Washington University studied 80 middle-aged participants, averaging 49 years old, with no cognitive impairment. Using MRI and PET scans, they examined the relationship between body fat types and Alzheimer’s-associated proteins like amyloid plaques and tau tangles.
“Higher visceral or hidden belly fat is the most important predictor of whole-brain amyloid and early tau protein accumulation,” explained Dr. Mahsa Dolatshahi, lead author of the study. These proteins are known hallmarks of Alzheimer’s and often appear years before cognitive decline becomes noticeable.
Other types of fat, including subcutaneous fat (the fat beneath the skin) and liver fat, showed no significant association with Alzheimer’s-related pathologies.
The Role of Metabolic Health
The study also highlights how metabolic health contributes to Alzheimer’s risk. Participants with higher insulin resistance and lower levels of high-density lipoprotein (HDL), or “good cholesterol,” were more likely to have elevated levels of amyloid plaques in their brains. “Managing Alzheimer’s risk in obesity will need to involve targeting the related metabolic and lipid issues,” said senior author Dr. Cyrus A. Raji.
Visceral fat, which surrounds critical organs, is already linked to inflammation and chronic diseases like diabetes and cardiovascular problems. According to neurologist Dr. Earnest Lee Murray, who was not involved in the study, “Inflammatory changes caused by visceral fat appear to extend to the brain, raising the risk of Alzheimer’s.”
A Path Forward for Prevention
With nearly three-quarters of Americans classified as overweight or obese, the findings carry significant public health implications. Around 6.9 million Americans aged 65 and older currently live with Alzheimer’s, a number expected to more than double by 2050.
“These findings suggest that early interventions like lifestyle changes or weight-loss medications could reduce cerebral blood flow issues and lower Alzheimer’s burden,” Raji noted. Regular exercise, a healthy diet, and managing conditions like diabetes and high blood pressure are proven strategies to reduce dementia risk, according to the Centers for Disease Control and Prevention.
Limitations and Future Research
Despite its promise, the study’s limitations include a small sample size and its cross-sectional design, which cannot confirm whether individuals with visceral fat and Alzheimer’s markers will develop symptoms. “We need further studies using PET scans to explore the role of body fat in Alzheimer’s disease,” Dolatshahi said.
Researchers are also exploring whether weight-loss drugs like GLP-1 medications could play a role in reducing visceral fat and improving brain health. “This study reinforces the importance of addressing risk factors early rather than waiting for symptoms to develop,” Murray added.
As science continues to unveil the hidden connections between the body and brain, understanding the role of visceral fat may prove crucial in combating the world’s most common form of dementia.
